Apparatus for producing sheet glass



Jan. 19, 1932. w. E. NQBBE 1,841,548

APPARATUS FOR PRODUCING SHEET GLASS Filed March v11-, 1930 Lu'llllam E.Nobbe Patented Jan. 19, 1932 NITED STATES PATENT OFFICE.

WILLIAM E. NOBBE, F TOLEDO, OHIO, ASSIGNOR TO LIBBEY-OWENS-FORD GLASSCOM- PANY, OF TOLEDO, OHIO, A CORPORATION OF OHIO AFJPARAT US FORPRODUCING SHEET GLASS Application filed March 11, 1930. Serial No.434,968.

The present invention relates to improvements in apparatus for producingsheet glass.

While this invention is herein illustrated and described as being usedin connection with the Colburn process for producing sheet glass asexemplified in Colburn Patent No.

1,248,809, granted December 4, 1917, it is of course not necessarilyrestricted to use in such connection, as it can well be adapted to othertypes of sheet glass forming apparatus.

An important object of the invention resides in the provision ofapparatus whereby the formation of surface defects or irregu larit iesin the sheet as it is being drawn will be reduced to a minimum so that aflatter, smoother, and more uniform thickness of sheet may be produced.

Another object of the invention is the provision of an apparatus forminimizing the formation of surface irregularities in the sheet duringthe formation thereof by subjecting opposite surfaces of said sheet to aT wiplng or smoothing action.

I A further object of the invention is the provision of means of a novelconstruction for engaging opposite surfaces of the sheet at the base ormeniscus thereof and also after it has attained sheet form forflattening or ironing out irregularities in the surfaces thereof.

Other objects and advantages of the invention will become more apparentduring the course of the following description when taken in connectionwith the accompanying drawings.

In the drawings wherein like numerals are employed to designate likeparts throughout the same:

Fig. 1 is a vertical longitudinal section through one type of sheetglass apparatus showing the present invention in use,

Fig. 2 is a perspective sectional view of the wiping or smoothingmembers,

Fig. 3 is an elevation showing one way in which the wiping members maybe mounted,

Fig. 4 is a sectional view of a slightly modified arrangement, and

Fig. 5 is a transverse section of a modified type of wiping member.

In the drawings, designates a glass sheet continuously drawn upwardlyfrom a bath of molten glass 11 contained in a work ing receptacle ordraw-pot 12 and supplied thereto from any suitable type of furnace 13.The sheet 10 is drawn vertically for a suitable distance and then whilestill in a semi-plastic condition is deflected about the rotatablebending roll 14 into a substantially horizontal plane, said sheet beingthen passed over a so-cal-led idler roll 15 and draw table 16 into andthrough an annealing leer, not shown.

In the Colburn process as ordinarily practiced, suitable knurled rollersor other width maintaining means are positioned to engage opposite edgesof the sheet atthe base thereof to prevent narrowing of the sheet as itis drawn upwardly. According to this invention, however, the usual sheetedge engaging means are omitted and there are substituted therefor thepreferably metallic members designated in their entirety 17 and 18 75respectively and which are positioned at opposite sides of the sheetadjacent to but spaced slightly above the molten mass 11. These membersextend the entire width of the sheet and serve not only to maintain saidsheet to width, but also to facilitate the drawing operation and toimprove the quality of the sheet produced. I

The members 17 and 18 are preferably construct-ed from a suitablenon-corrosive metal such as Monel, nichrome, etc., with each memberbeing in the form of a substantially U- shaped hollow casing andcomprising the substantially vertical portion 20 and the inwardlydirected portions 21 and 22 at the top and bottom thereof respectively.Each member may also be divided intermediate the upper and lower endsthereof by means of a horizontal partition wall 23 to provide separateupper and lower chambers 24 and 25 through which a suitable coolingmedium is adapted to be circulated. By dividing each member into upperand lower chambers, a different type of cooling medium may be circulated100 different temperatures.

When the members 17 and 18 are positioned at opposite sides ofthe sheet10 in the manner illustrated in Fig. 1, it will be seen that theinwardly directed portions 22 of said members engage the base ormeniscus 19 thereof, while the inwardly directed portions 21 engage thesheet after it has attained final sheet form. Thus, the inwardlydirected portions 21 are longer than portions 22 so that the spacebetween adjacent portions 22 is greater than that between adjacentportions 21. As the glass is drawn upwardly between members 17 and 18,the opposite surfaces thereof will be submitted to a wiping or smoothingaction first by the inwardly directed portions 22 and then by theinwardly directed portions 21 which will tend to fiatten or iron out anyirregularities or defects in the surfaces thereof so that a flatter,smoother sheet of glass of a more uniform thickness will be produced.The inturned end portions 22 are adapted to be arcuately curved so thatthey fit substantially into the curvature of the sheet meniscus 19,while the portions 21 are adapted to be curved so that they havesubstantially line contact with the sheet to reduce the area of contactbetween the sheet and metal members at this point.

The members 17 and 18 further cooperate with one another to shield thesheet during its formative period so asto protect it from hot gases,cold drafts and other atmospheric changes. Thus, said members cooperateto provide a substantially closed compartment 26 through which the sheetis drawn in its early formative stage. If desired, the members 17 and 18may be relatively taller than as shown by the full lines, in Fig. 1 and,as a matter of fact, may extend substantially up to the bending roll 14as indicated by the broken lines so as to shield the sheet during agreater portion of its upward travel and so that the portions 21 willengage the sheet at a point more closely adjacent the bending roll. Attimes, it may be found desirable that the inwardly directed portions 22engaging the sheet meniscus be maintained at a different temperaturethan the portions 21 engaging the sheet after it is formed and this canbe readily accomplished by dividing the members 17 and 18 horizontallyinto upper and lower chambers 24 and 25 as described hereinabove andthen independently circulating a different temperature control mediumthrough said chambers or the same medium at different temperatures. Ofcourse, the partitions 23 maybe eliminated if desired.

One way in which the members 17 and 18 may be mounted is illustrated inFig. 3.

Thus, the member 17 is provided at each end thereof with the verticallyaligned tubular extensions 27 carried by a support 28 fixedly securedtoa base 29. On the other hand, the

member 18 is provided at each end thereof with the tubular extensions 30carried by a support 31 slidably mounted upon base 29 and normally urgedtoward member 17 by a compression spring 32. However, the inwardmovement of member 18 is controlled by proper adjustment of the nut' 33upon bolt 34, which bolt is carried by support 31 and projects outwardlythrough fixed bracket 35. Thus, while the member 18 is yieldably urgedtoward member 17, it can be readily moved away therefrom to allow forthe passage of clay particles or other foreign matter therebetween whichmay be carried upwardly by the sheet.

The arrangement disclosed in Fig. 4 is substantially the same as thatshown in Fig. 1, with the principal exception that instead of providingtwo substantially U-shaped members having a partition wall intermediatethe upper and lower ends thereof, there are here provided fourindividual members 36, 37, 38, and 39. The members 36 and 37 arearranged at one side of the sheet, while the members 38 and 39 arearranged at the opposite side. It will be seen, however, that these fourmembers are arranged in the same manner and cooperate with one anotherin the same way to accomplish the same results as do the twosubstantially U-shaped members 17 and 18.

In Fig. 5, the wiping members 40 and 41 positioned at opposite sides ofthe sheet are of a slightly different type. Each of these members is inthe form of asubstantially rectangular hollow casing through which isadapted to be circulated a suitable cooling medium. However, the upperportion 42 of the inner wall of each member is arcuately curved andpositioned to contact with the sheet, while the lower portion 43 isspaced 'from the sheet and substantially parallel therewith. Thesemembers are not adapted to engage the sheet until it has attained finalsheet form and the portions 42 are adapted to be arcuately curved sothat they have substantially line contact therewith. The portions 42engaging the sheet will have a Wiping or smoothing action thereon tosmooth or flatten out any surface irregularities therein, while thelower portions 43 of the members will serve as shields to protect thesheet during its formative period.

It is to be understood that the form of the invention herewith shown anddescribed is to be taken as the preferred embodiment of the same, andthat various changes in the shape, size and arrangement of-parts mayberesorted to without departing from the spirit of the invention or thescope of the subjoined claims.

. I claim:

1. 1n sheet glass apparatus, means for surfaces of the sheet at the baseor meniscus thereof and also after it has attained sheet form forproducing a wiping action thereupon to flatten or smooth out anyirregulari-.

tioned at opposite sides of the sheet and engaging the same at the baseor meniscus thereof and also after it has attained sheet form forproducing a wiping action thereupon to flatten or smooth out anyirregularities in the surfaces thereof.

3. In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten glass, and members having portions engaging oppositesurfaces of the sheet at the base or meniscus thereof and also havinportions engaging opposite surfaces of sai sheet after it has attainedsheet form for produc ing a wiping action thereupon to flatten or smoothout any irregularities in the surfaces thereof.

4. In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten glass, and members having portions engaging oppositesurfaces of the sheet at the base or meniscus thereof and also havingportions engaging opposite surfaces of said sheet after it has attainedsheet form for producing a wiping action thereupon to flatten or smoothout any irregularities in the surfaces thereof, said first mentionedportions being curved to fit substantially into the curvature of thesheet meniscus, with said second mentioned portions being curved to havesubstantially line contact with the sheet.

5. In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten. glass, and a pair of stationary members positioned atopposite sides of the sheetand engaging the same for producing a wipingaction thereupon to flatten or smooth out any irregularities in thesurfaces thereof, said members having inwardly directed portionsengaging opposite surfaces of the sheet at the base or meniscus thereofand also havin wardly directed portions engaging the s eet after it hasattained sheet form.

6; In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten glass, and a pairof stationary members positioned atopposite sides of the sheet and engaging the same for producing a. wip--ing action thereupon to flatten or smooth out any irregularities in thesurfaces thereof, said members having inwardly directed portionsengaging opposite surfaces of the sheet at the ase or meniscus thereofand also having inwardly directed portions engagingthe sheet after ithas attained sheet form, the first mentioned inwardly directed portionsbeing spaced further apart than said second mentioned inwardly directedportions.

7. In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten glass, and a pair of stationary members positioned atopposite sides of the sheet and engaging the same for producing a wipingaction thereupon to flatten or smooth out any irregularities in thesurfaces thereof, each of said members comprising an inwardly directedportion engaging the base or menlscus of the sheet, an inwardly directedportion engaging the sheet after it has attained sheet form, and avertically disposed portion connecting the two inwardly directedportions and spaced from said sheet.

8. In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten glass, a pair of hollow stationary members positioned atopposite sides of the sheet and engaging the same for producing a wipingaction thereupon to flatten or smooth out any irregularities in thesurfaces thereof, each of said members comprising an in wardly directedportion engaging the base or meniscus of the sheet, an inwardly directedportion engaging the sheet after it has attained sheet form, and avertically disposed portion connecting the two inwardly directedportions and spaced from said sheet, a horizontal partition forseparating the vertically disposed portion of each member horizontallyintermediate its upper and lower ends, and separate means forindependently circulating a temperature control medium through saidmembers above and beneath said partition. 1

9. In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten glass, hollow member's positioned to engage oppositesurfaces of the sheet adjacent to but spaced above the molten mass forproducing a wiping action thereupon to flatten or smooth out anyirregularities in the surfaces thereof, a horizontal partition dividingeach member into upper and lower chams bers, and separate means forindependently circulating a temperature control medium through saidchambers.

10. In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten glass, and members positioned to engage opposite sides ofthe sheet adjacent the molten mass for producing a wiping actionthereupon to flatten or smooth out any irregularities in the surfacesthereof, said members having portions thereof engaging the sheet andportions spaced therefrom and cooperating to form a substantially closedcompartment through which the sheet is drawn during itsformative period.

11; In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten glass, and substantially U-shaped members positioned atopposite sides of the sheet adjacent the molten mass, each membercomprising a substantially vertically diswardly directed upper and lowerportions in eontact with saidsheet for producing a wiping actionthereupon to flatten or smooth out any irregularities in the surfacesthereof.

12. In sheet glass apparatus, means for drawing a sheet'upwardly from amass of molten glass, and substantially U-shaped members positioned atopposite sides of the sheet adjacent the molten mass, each membercomprising a substantially vertically disposed portion spaced from thesheet and inwardly directed upper and lower portions in contact withsaid sheet for producing a wiping action thereupon to flatten or smoothout any irregularities in, the surfaces thereof, the upper portionsprojecting inwardly to a greater degree than the lower portions.

13. In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten glass, and stationary substantially U-shaped members inthe form'of hollow metallic casings positioned at opposite sides of thesheet adjacent to but spaced above the mol en mass, each membercomprising a substantially vertically disposed portion spaced from thesheet, an inwardly directed lower portion engaging the sheet at the baseor meniscus thereof, and an upper inwardly directed portion engaging thesheet after it has attained sheet form, said members cooperating toprovide a substantially closed compartment through which the sheet isdrawn during its formative period. v j

14. In sheetu glass apparatus, means for drawing a sheet upwardly from amass of molten glass, statlonary substantially U- mentioned portionsarranged out of contact with said sheet and acting to shield the same. 7

16. In sheet glass apparatus, means for drawing a sheet upwardly from amass of molten glass, and stationary members positioned at oppositesides of the sheet and having portions spaced from the sheet andarranged substantially parallel therewith in a manner to shield thesame'and also laterally oifset portions in contact with said sheet forproducing a wiping action thereupon to flatten or smooth outirregularities in the surshaped members in the form of hollow metalliccasings positioned at opposite sides of the sheet adjacent to but spacedabove the molten mass, each member comprising a sub- ,stantiallyvertically disposed portion spaced from the sheet, an inwardly directedlower portionengaging the sheet at the base or meniscus thereof, and anupper'inwardly directed portion engaging the sheet after it has attainedsheet form, said members cooperating to provide a substantiallyclosedcompartment through which the sheet is drawn during its formativeperiod,'a horizontal partition separating the interior of each memberintermediate its upper and lower ends into upper and lower chambers, andseparate means for independently circulating a temperature controlmedium through said chambers.

15. In sheet glass apparatus, means for drawing% sheet upwardly from amass of molten glass, and stationary members positioned at/oppositesides of the sheet and havtate of Ohio, this 10th day of March

